Text and, to a lesser degree, speech chatting systems, are generally known in the art, particularly in relation to personal computing systems. Published U.S. Patent Application Nos. 2001/0042095 A1; 2001/0011293 A1; and 2002/0023128 A1 and U.S. Pat. Nos. 6,212,548 and 6,286,034 illustrate exemplary system and user interfaces used today. A common feature of such systems is that the various conversations (or threads) are usually split out into distinct regions (or windows) on the display or screen. Furthermore, when a single thread comprises a plurality of both text and speech exchanges, such systems usually separate the two modalities. The speech is usually played over a speaker, whereas the plurality of text messages are displayed on the screen. Users have no means to reference old speech messages or distinguish when they occurred in the thread relative to other messages in that thread.
Published U.S. Patent Application No. 2002/0023128 A1 (“the '128 Publication”) describes a system where the screen area is split into six distinct windows. One window presents a chat history of one thread (the thread in focus) while another window displays a chat history of the combined plurality of the remaining threads. A chat history comprises a plurality of entries displayed on the screen that describe both inbound (i.e., received by the user's mobile terminal) and outbound (i.e., sent by the user's mobile terminal) chat messages. The entries are usually displayed on the screen in chronological order and usually only describe text messages.
Although the above described chat systems fulfill the needs of some chat group users, they focus primarily on large screens such as those found on personal computers. Viewable regions on the screen are dedicated to particular functionality. Such interfaces are not well suited for devices where the display area is small. On small screen devices, such as mobile devices, dedicating a region exclusively for text entry or other transient functionality consumes precious screen area. Such schemes do not allow the device to take full advantage of available screen display area when transient functionality (e.g., editing a new message.) is not in use.
Common practices on mobile device today usually transition the user through a series of screens. For example, when it is time to edit a message, the conventional practice on limited screen devices is to move the user from a chat history screen that occupies the entire content display region of the screen to a text editing screen, which also occupies the content display region of the screen. Such schemes do not allow a user to view a chat history as it progresses in real time while the user composes a message. When there is an incoming message, the user must move back to the history screen to see if the message currently being composed is still relevant given the context of messages received. A user interface that addresses such issues greatly enhances the desirability and convenience of participating in a chat session. Therefore, there is a need to provide a wireless chat messaging system that has an improved user interface at the mobile units, which permits the simultaneous display of chat threads and composition and/or editing of response messages on demand, taking into account limitations of mobile devices.